The agreement allows Schulze, the company's biggest shareholder, to wait until the end of the holiday season and fiscal year before making an offer.
In a statement, Best Buy said the extension "is in the best interests of shareholders" and will give Schulze and potential partners more time for due diligence on the company.
Shares of the company, which rose Thursday on news of an imminent buyout offer, fell $2.08, or 14.7%, to $12.04 in mid-session trading Friday.
Under the new terms, Schulze can make a proposal anytime in February, extending his previous deadline of mid-December. Then the board of directors will have 30 days to consider the offer.
In August, Schulze had offered to take the company private for $24 to $26 a share, a deal that could have been worth as much as $8.84 billion. Best Buy eventually agreed to open its books so Schulze could dig deeply into its finances before making another offer.
Complicating any potential deal is the relationship between Schulze and Best Buy's board, which Schulze led as chairman until a scandal involving its then-chief executive forced him to step down in June.
In April, Brian Dunn, then Best Buy's chief executive, resigned amid allegations that he engaged in an inappropriate relationship with a female employee. The board then voted to oust Schulze after an internal investigation revealed that he had known of Dunn's indiscretions months earlier and failed to take action.
Schulze remains the company's largest stakeholder with 20% of its shares.
Even if the 71-year-old Schulze succeeds in taking Best Buy private, he'll be taking over a company and a competitive landscape that looks nothing like they did when he founded the chain in 1966.
The company, based near Minneapolis, is the biggest survivor of the consumer electronics shakeout that saw the demise of Circuit City and a host of regional competitors. But the slowing market for DVDs and CDs and competition from online rivals have dimmed its prospects.
Despite its turnaround efforts, industry watchers speculate that Best Buy may eventually go the way of Circuit City, the former rival that closed its last store in 2009.
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